Foldable single parallel bar with adjustable height

A foldable single parallel bar with adjustable height, comprising:

• a bottom horizontal pipe, which extends in a left-and-right direction;
• two bases, which are respectively provided at two ends of the bottom horizontal pipe, and the bases are configured to rotate relative to the bottom horizontal pipe around a rotation axis extending in a front-and-back direction;
• rotation axes of the two bases have a height difference that avoids each other;
• a main pillar, which is fixed on the bases and folds together with the bases;
• two auxiliary pillars, which are sleeved by the main pillar and are configured to freely expand and contract in a vertical direction within the main pillar;
• upper ends of the two auxiliary pillars are detachably fixed with a horizontal bar, and there is a locking member between the auxiliary pillars and the main pillar that restricts free expansion and contraction of the auxiliary pillar within the main pillar;
• foot supports, which are respectively provided on front and rear sides of the bases, and the foot supports are configured to rotate relative to the bases around a rotation axis extending in the left-and-right direction, and then fold together with the bases.